We are already seeing the first examples of how climate change will leave us all thirsty

Chelsea Harvey, provided by

Published 7:25 am, Tuesday, March 3, 2015

Climate change is reshaping the planet in a big way.

Rising temperatures, melting ice, and surging seas are just a few of the obvious effects that we're already observing.

And, according to recent climate reports, these events could bring on a whole host of other consequences, including bigger storms, increases in infectious disease, shifts in plant and animal life, famines, droughts, and even increased poverty and civil unrest.

In fact, climate change is threatening one of our planet's most precious and necessary resources: our water.

We don't mean the oceans, although climate-caused water warming and ocean acidification are going to be big problems too. We're talking about our freshwater resources — the water we depend on for drinking, bathing, and nourishing our crops, which can't grow in salt water.

Higher temperatures can increase the chance of drought, making water scarce. Hotter weather also means people, animals, and even plants need to take in bigger volumes of water to avoid dehydration, putting a strain on the water supplies that already exist. On top of that, sea-level rise in coastal areas can allow salty ocean water to contaminate freshwater aquifers, which many coastal communities rely on for their drinking water.

How serious the water problem gets — along with all the other climate-related effects — depends on whether humans can buckle down and start cutting the amount of carbon dioxide and other greenhouse gases we use currently pour into the atmosphere.

In some places around the world, we're already seeing the first examples of how climate change could leave us all thirsty. Here are just a few:

Higher temperatures have big implications for the amount of water we use. Hot weather makes people more likely to get dehydrated, meaning they tend to use more water than they would in milder conditions. People also often use more water in hot weather to water their plants or to irrigate crops.

As temperatures continue to climb, we could see an increased demand for freshwater, even as our supplies begin to dwindle.

Drought

Rising temperatures won't only increase our demand for freshwater — they can also deplete our supplies of it. As the Earth continues to warm, scientists predict we'll see an increase in droughts. To imagine what that might feel like, we can look back at 2014, which was a big year for drought around the world.

Not all of these past droughts can be definitively blamed on global climate change — for example, a recent study by NOAA suggests that California's extended drought (currently in its fourth year) was not caused by climate change. But in the future, climate change is likely to bring on more of these same types of multi-year, or even multi-decade, droughts.

Rising temperatures can also deplete freshwater supplies in other ways. Some areas rely on mountain snowpack for some of their freshwater supplies. In parched California, for example, snow that accumulated in the mountains during the winter provides up to a third of the state's water supply, melting in the spring and trickling down to lower areas.

But, according to California's Department of Water Resources, climate change will likely result in smaller snow accumulations and cause any existing winter snowpack to melt earlier and faster in the future, making it harder to capture and store. The state expects to lose at least a quarter of its Sierra mountains snowpack by 2050, a major blow to California's freshwater supplies.

Sea-level rise

The phrase "sea-level rise" tends to evoke visions of flooding and erosion. These are some of its major consequences, but other effects are more subtle.

One major concern about the rising seas is that they will start to intrude on coastal aquifers — the underground pockets of freshwater that many coastal communities rely on for their drinking water supplies.

Once the saltwater creeps in and contaminates the aquifers, the water either cannot be used or must be desalinated, a costly and energy-consuming process. This is a not-so-distant concern, either — the Intergovernmental Panel on Climate Change predicts that sea level could rise by a meter or more by the end of the century.

Bangladesh is a prime example of how rising sea levels are already threatening everyday life. A low-lying country prone to flooding, Bangladesh is one of the world's most vulnerable nations when it comes to sea-level rise. A study from the World Bank concluded that the encroaching sea could significantly change the saltwater content of Bangladesh's rivers, which could cut down on the nation's drinking water supplies.

These are just a few examples of the ways climate change is already making itself apparent in our water sources around the world. As things continue to heat up on our warming planet, we could all end up very thirsty, indeed.